The proposed project will apply techniques developed in cognitive neuroscience to examine brain activities involved in the processing of expectancies (e.g., traits and stereotypes) and expectancy violations in person perception. Several theoretical models posit that expectancy- violating information receives different or more elaborative cognitive processing than expectancy-consistent information. Other models propose that processing of social information differs depending on its affective tone, or valence. Finally, research suggests that alcohol intoxication leads to working memory impairments that may create greater conflict in the processing of information that violates an established context, such as a social expectancy. Measures of neurophysiological activity associated with information processing, such as event-related brain potentials (ERPs) and event-related optical signal (EROS), have the potential to provide new perspectives on the manner in which information about people is processed, as well as the variables that may significantly influence this processing. In the proposed research, ERPs and EROS will be used to specify 1) the time course and the level of engagement of information processing operations related to expectancy violations and the valence of behavior, 2) potential differences in the processing of trait-based versus stereotype-based expectancy information, 3) potential effects of alcohol intoxication on the processing of expectancy violations, and 4) the cortical area(s) involved the processing of expectancy-relevant information.